From 7cf3b1dd6aa603fd80969e9e7160becf1455a0eb Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Mon, 15 Mar 2021 13:04:37 -0700 Subject: Bluetooth: L2CAP: Fix not checking for maximum number of DCID When receiving L2CAP_CREDIT_BASED_CONNECTION_REQ the remote may request more channels than allowed by the spec (10 octecs = 5 CIDs) so this checks if the number of channels is bigger than the maximum allowed and respond with an error. Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Marcel Holtmann --- net/bluetooth/l2cap_core.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'net/bluetooth/l2cap_core.c') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 72c2f5226d67..374cc32d7138 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5921,7 +5921,7 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, struct l2cap_ecred_conn_req *req = (void *) data; struct { struct l2cap_ecred_conn_rsp rsp; - __le16 dcid[5]; + __le16 dcid[L2CAP_ECRED_MAX_CID]; } __packed pdu; struct l2cap_chan *chan, *pchan; u16 mtu, mps; @@ -5938,6 +5938,14 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, goto response; } + cmd_len -= sizeof(*req); + num_scid = cmd_len / sizeof(u16); + + if (num_scid > ARRAY_SIZE(pdu.dcid)) { + result = L2CAP_CR_LE_INVALID_PARAMS; + goto response; + } + mtu = __le16_to_cpu(req->mtu); mps = __le16_to_cpu(req->mps); @@ -5970,8 +5978,6 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, } result = L2CAP_CR_LE_SUCCESS; - cmd_len -= sizeof(*req); - num_scid = cmd_len / sizeof(u16); for (i = 0; i < num_scid; i++) { u16 scid = __le16_to_cpu(req->scid[i]); -- cgit v1.2.3-59-g8ed1b